Caption: Fossil hominid skull of a robust australopithecine known as Australopithecus boisei (KNM-ER 406) found in Koobi Fora region, Lake Turkana, north- east Kenya. The skull was excavated in 1969 during an expedition led by Richard Leakey. This find confirmed that the robust australopithecines inhabited a wide expanse of southern and eastern Africa from about 2.5 until 1.6 million years ago, after which they became extinct. The skull is heavily built with a broad face, small neurocranium and sagittal crest (top). It also shows occipital and supramastoid crests which are associated with a heavy mandible and powerful muscles for chewing. A. boisei was a vegetarian.